| Details | |
|---|---|
| Duration | 28 January 1991 – 22 December 1991 |
| Edition | 14th |
| Tournaments | 95 |
| Achievements (singles) | |
← 1990 1992 → | |
The ATP Challenger Series is the second tier tour for professional tennis organised by the Association of Tennis Professionals (ATP). The 1991 ATP Challenger Series calendar comprised 94 tournaments, with prize money ranging from $25,000 up to $100,000.[1][2]